An Electrochemical and XRD Study of Lithium Insertion into Mechanically Alloyed Magnesium Stannide

An Electrochemical and XRD Study of Lithium Insertion into Mechanically Alloyed Magnesium Stannide

TitleAn Electrochemical and XRD Study of Lithium Insertion into Mechanically Alloyed Magnesium Stannide
Publication TypeJournal Article
Year of Publication2003
AuthorsGregory A Roberts, Elton J Cairns, Jeffrey A Reimer
JournalJournal of The Electrochemical Society
Volume150
Issue7
PaginationA912-A916
ISSN00134651
Keywordselectrochemical electrodes, intercalation compounds, lithium alloys, magnesium alloys, mechanical alloying, tin alloys, x-ray diffraction
Abstract

The intermetallic Mg2Sn is a promising negative electrode material for rechargeable lithium cells. Preliminary cycling tests have demonstrated stable capacities at 400 mAh/g for 20 cycles. Magnesium stannide was produced by mechanically alloying magnesium and tin powders. Mechanical alloying can convert the equilibrium Mg2Sn phase to a metastable phase by the introduction of defects with extended milling times. In situ X-ray diffraction has shown that the cubic Li2MgSn phase, which is similar in size and structure to cubic Mg2Sn, is produced by lithium insertion into the equilibrium and metastable phases. The conversion from the metastable phase is irreversible, so subsequent lithium removal from Li2MgSn produces the equilibrium Mg2Sn phase.

DOI10.1149/1.1578477
Short TitleJ. Electrochem. Soc.